Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Nano Lett. 2010 Nov 10;10(11):4584-9. doi: 10.1021/nl102594e. Epub 2010 Oct 12.
The deposition of n-GaAs shells is explored as a method of n-type doping in GaAs nanowires grown by the Au-mediated metal-organic chemical vapor deposition. Core-shell GaAs/n-GaAs nanowires exhibit an unintended rectifying behavior that is attributed to the Au diffusion during the shell deposition based on studies using energy dispersive X-ray spectroscopy, current-voltage, capacitance-voltage, and Kelvin probe force measurements. Removing the gold prior to n-type shell deposition results in the realization of n-type GaAs nanowires without rectification. We directly correlate the presence of gold impurities to nanowire electrical properties and provide an insight into the role of seed particles on the properties of nanowires and nanowire heterostructures.
研究了通过 Au 介导的金属有机化学气相沉积生长的 GaAs 纳米线中 n-GaAs 壳层的沉积，作为 GaAs 纳米线 n 型掺杂的方法。基于能量色散 X 射线光谱、电流-电压、电容-电压和 Kelvin 探针力测量的研究，GaAs 核壳纳米线表现出意外的整流行为，这归因于在壳层沉积过程中的 Au 扩散。在进行 n 型壳层沉积之前去除金，可实现无整流的 n 型 GaAs 纳米线。我们将金杂质的存在与纳米线的电特性直接相关，并深入了解了种子颗粒对纳米线和纳米线异质结构性质的作用。
